Channel ui changes.

[vexorian]

Here's some improvements to the channel UI including some weird ideas.

• Confirmation popup when deleting channels.
• Button to delete all programs in a channel: I've been in dire need of something like this because I use playlists to keep track of what should be in a channel, it's easiest to just remove everything and add the playlist. I'm not sure if the location I picked is the best place for it.
• "Cyclic Shuffle": I couldn't think of a good name for this. But the idea is that this is a shuffle that preserves the relative sequence between a show's episodes. So the order between tv shows is random, but the episodes of a TV show will be in the correct order. If a tv show has repeated episodes, the order will be cycled. So for example, if a show with four episodes is repeated 3 times, the episodes will play in this sequence: 1-2-3-4-1-2-3-4-1-2-3-4- Okay it's hard to explain, so here's an example: https://imgur.com/a/RiTcCN0

And the most controversial change:

When opening an existing channel, it will now adjust the channel's starting time and rotate the list of programs so that the program that's currently on air will be the first one on the list, and the channel's start time will match the program's start time.

So for example, if you created a channel a week ago and it alternates between 3 episodes of one hour each. The next time you open the channel, the starting time of the channel will be adjusted to the last hour, and if the third episode is currently playing, the program list will be changed tro 3-1-2 , instead of 1-2-3.

There are two benefits from doing this:

• You can now use the channel editor as a TV guide, because it will let you know which program is currently on air and which programs will air after it.
• It allows you to add a new program without altering the short-term timeline at all.

The con is of course that after saving a channel, the rotation and starting time will keep changing, and the first times this happens people might think some programs went missing (but in reality they need to scroll down to find them in the future schedule). I added a note to explain user what happened there.

[vexorian]

I've made some changes to the contents of the PR.

First all, the cyclic shuffle will now consider specials (season 0) as if they were movies and it will place them at random locations. specials make more sense this way. Otherwise you'd have all specials playing in a row even though they normally don't have such ordering logic.

The change to the channel view, when loading the channel and changing the start time, it will now remove the milliseconds from the start time. It adds the milliseconds again when saving. This is mostly so that users don't have to think about milliseconds when designing their channels.